Surgical retractor systems and illuminated cannulae

ABSTRACT

This invention includes surgical retractors that comprise an expandable frame that includes at least two base components, a connector, and at least two retractor blades attached to the expandable frame. Also included are surgical retractors that comprise a housing component that includes a cylindrical portion and a contiguous blade portion, assemblies comprising a surgical retractor assembled to at least one obtruator, illuminated surgical cannulas, and methods of using the same during a surgical procedure.

REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent ApplicationNo. 60/530,565, filed on Dec. 18, 2003, which is incorporated herein byreference.

BACKGROUND

In surgical procedures, it is preferable to minimize or reduce trauma tothe patient and damage to tissue. To achieve this result, surgeons tryto keep incisions as small as possible. However, it is usually necessarythat the surgeon have a clear view of the operating field.

A variety of retractors are available to keep an incision open andprovide a clear view of the operating field. Retractors are used insurgical operations to reposition muscular tissue, vessels, nerves, andother tissue with the aid of retractor blades, thereby providing accessto the site of the operation. Surgical retractors are particularlyimportant in performing surgical procedures that involve the spinalcolumn, where access to the surgical sight can be obtained, for example,through a posterior, posterior-lateral, anterior, lateral, or ananterior-lateral approach.

In some embodiments, a step-wise dilation of the surgical incision canbe performed to gradually dilate the muscles and tissues to the requiredsize to insert the retractor. Step-wise dilation can involve the use ofa series of dilators or cannulae with successively larger diameters.This method involves first inserting the smallest dilator or cannulainto an incision. Then a second dilator or cannula, with a slightlylarger diameter, is slid over the smaller dilator or cannula and intothe incision, thereby causing the incision to expand to the slightlylarger diameter of the second dilator or cannula. This process can berepeated using a series of dilators or cannulae with successively largerdiameters, until the incision is large enough to allow for insertion ofthe retractor. Once positioned, the retractors produce a small surgicalsite or window. However, most currently available retractors are largeand cumbersome, requiring a long incision length that traumatizes thepatient's muscles and tissue.

Therefore a need exists for a retractor that overcomes or minimizesthese and other problems.

SUMMARY

Disclosed herein are methods and devices that improve surgicalprocedures by, for example, creating a working space for the procedureand improving the surgical conditions for a practitioner of theprocedure.

This invention includes surgical retractors. In some embodiments, thesurgical retractor comprises a frame and at least two retractor bladesattached to the frame. The frame includes a first base component, asecond base component, and a connector. The connector connects the firstbase component and the second base component, and the first basecomponent and/or the second base component are moveable along a lengthof the connector. Upon movement of the connector relative to the firstbase component or second base component, the frame moves from a firstposition to a second position and causes a distance between the firstbase component and the second base component to change; and

In other embodiments, the surgical retractors of the invention comprisea first retractor blade, a second retractor blade, a third retractorblade, a fourth retractor blade, a first connector, and a secondconnector. The first connector is assembled to a proximal end of thefirst retractor blade and a proximal end of the second retractor blade,and the first retractor blade and/or the second retractor blade ismovable along a line that is parallel to a length of the firstconnector. The second connector is assembled to a proximal end of thethird retractor blade and a proximal end of the fourth retractor blade,and the third retractor blade and/or the fourth retractor blade ismovable along a line that is parallel to a length of the secondconnector. The first connector and/or the second connector is movablealong a line that intersects the first connector and the secondconnector.

In another embodiment, this invention includes an assembly comprising asurgical retractor (e.g., a surgical retractor of the invention)assembled to an obtruator.

In yet more embodiments, the surgical retractors of the inventioncomprise a housing component having a central axis and a cylindricalexpander component. The housing component includes a cylindrical portionand a blade portion. The cylindrical portion defines a conduit having aninner diameter normal to the central axis. The blade portion iscontiguous with one end of the cylindrical portion and includes at leasttwo blades. A distal portion of each blade is moveable relative to thecentral axis. In a first position, the distal ends of the blade portionare proximate, and upon movement of the distal portion of the bladesrelative to the central axis, the blades move from a first position to asecond position and form a conduit down the length of the central axis.The cylindrical expander portion has an outer diameter that is smallerthan the inner diameter of the cylindrical portion and the expandercomponent is movably attached to the housing component.

In still more embodiments, this invention includes an illuminatedsurgical cannula comprising a surgical cannula and an interface ring.The surgical cannula has an outer diameter, an inner diameter, a distalend, and a proximal end, wherein an interior area is defined by theinner diameter, the distal end, and the proximal end. The interface ringis attached to the proximal end and includes a light source interface inphotonic communication with an array of fiber optic wire. The array isarranged to direct light towards the distal end of the cannula.

In yet further embodiments, this invention includes surgical methods.The methods comprise incising tissue of a mammal to create an incision,expanding the incision to create a pathway from the incision to asurgical site, directing a retractor (e.g., a retractor of theinvention) into the pathway, creating a working channel through theretractor by separating at least two retractor blades, and performing atleast a portion of a surgical procedure through the working channel. Insome embodiments of the invention, the pathway extends to a firstvertebra and at least a portion of the surgical procedure is performedat the first vertebra, and the method further includes directing aninstrument or implant between at least two retractor blades to access asecond vertebra adjacent to the first vertebra. In still furtherembodiments, the retractor is expanded by separating a first retractorblade from a second retractor blade by moving at least one of the firstretractor blade and the second retractor blade along an first connectorof the retractor and separating a third retractor blade from a fourthretractor blade by moving at least one of the third retractor blade andthe fourth retractor blade along a second connector, wherein the secondconnector is oriented at an angle to the first connector.

The retractors of this invention can be inserted into a body with theease of a tubular-based system (e.g., a step-wise dilation system),while allowing the surgeon to further retract tissue and muscle once theretractor is located at its fixed position in the body. This inventionallows the insertion of a retractor with either step-wise dilation of aminimally invasive incision (e.g., a stab incision), by, for example,inserting the retractor over one or more dilators or without step-wisedilation of the incision by, for example, inserting the retractorthrough an open incision or through a minimally invasive incision thatis expanded by methods other than sequential dilation. The inventionprovides methods and devices that reduce the invasiveness and traumaassociated with surgical procedures. The illuminated cannula of thisinvention eliminate the need for light sources that restrict the workingspace.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a view of a portion of one embodiment of a retractorof the invention.

FIG. 2 illustrates a view of a partially disassembled portion of oneembodiment of a retractor of the invention.

FIG. 3 illustrates a portion of a first base component of one embodimentof the invention.

FIG. 4 illustrates a ratchet release button of one embodiment of theinvention.

FIG. 5 illustrates a second base component of one embodiment of theinvention.

FIGS. 6-8 illustrate one embodiment of a retractor of the invention inthree different positions or degrees of expansion.

FIGS. 9-12 illustrate four different views of one embodiment of aretractor of the invention.

FIGS. 13A-13C illustrate the inner face of a blade of one embodiment ofthe invention with a blade extension at progressively longer telescopiclengths.

FIG. 14 illustrates a close up view of the distal end of the outer faceof the blade extension shown in FIGS. 13A-13C.

FIG. 15 illustrates one embodiments of a retractor of the invention thatincludes blade extensions.

FIG. 16A-16M illustrates another embodiment of a retractor of theinvention.

FIGS. 17A-17C illustrate various blade shapes for some embodiments ofretractors of the invention.

FIGS. 17D-17F illustrate optional blade features for some embodiments ofretractors of the invention.

FIG. 18 illustrates one embodiment of a retractor of the invention.

FIG. 19 illustrates one embodiment of a retractor of the invention.

FIG. 20 illustrates one method of attaching additional blades to oneembodiment of a retractor of an invention.

FIGS. 21A-21D illustrates one embodiment of a retractor of theinvention.

FIGS. 22A-22H illustrate one embodiment of a method used to retracttissue near the spine of a human.

FIG. 23 illustrates one embodiment of an insertion tube.

FIG. 24 illustrates another embodiment of an insertion tube.

FIG. 25 illustrates one embodiment of an assembly of the invention thatincludes a retractor positioned over an obtruator and a series ofdilators.

FIG. 26 illustrates one embodiment of a distraction instrument.

FIGS. 27 and 28 illustrate one method of expanding one embodiment of aretractor of the invention with one embodiment of a distractioninstrument.

FIGS. 29 and 30 illustrates one embodiment of a retractor of theinvention.

FIG. 31 illustrates one embodiment of a retractor of the invention withdistal ends at a first position and FIG. 32 illustrates the retractorwith distal ends at a second position.

FIG. 33 illustrates the retractor shown in FIGS. 31 and 32 with oneembodiment of an attached expander component.

FIG. 34 illustrates one embodiment of an interface ring.

FIG. 35 illustrates a portion of one embodiment of a cannula of theinvention.

FIG. 36 illustrates the interface ring of FIG. 34 assembled to a portionof the cannula of FIG. 35.

FIGS. 37A-37U illustrate embodiments of the invention that include amethod of using a retractor (e.g., a retractor of the invention) duringa surgical procedure on the spine of a human and related instruments andtools.

DETAILED DESCRIPTION OF THE INVENTION

A description of preferred embodiments of the invention follows. Whilethis invention has been particularly shown and described with referencesto preferred embodiments thereof, it will be understood by those skilledin the art that various changes in form and details may be made withoutdeparting from the scope of the invention encompassed by the appendedclaims.

This invention includes surgical retractors that provide a surgicalsite. In some embodiments, the surgical retractor comprises anexpandable frame attached to at least two retractor blades.

In some embodiments, the retractors include an expandable frame. Theexpandable frame includes two or more base components and at least oneconnector that connects the base components (e.g., 3, 4, 5, 6, 7, 8, ormore than 8 base components and/or connectors). At least two of the basecomponents are connected by one or more connectors (e.g., a ratchet armor a hinge) that are moveable relative to at least one base component.

Upon movement of the connector relative to at least one base component,the expandable frame moves from a first position to a second position,thereby causing an average distance between the base components toincrease or decrease (i.e., the expandable base expands or contracts),Moving the connectors relative to at least one base component causes theexpandable frame to move from a first position to a second position,thereby causing an average distance between the base components toincrease or decrease. Moving the same, or another, connector relative tothe same, or another, base component causes the expandable frame to movefrom the second position to a third position or back to the firstposition, thereby causing the average distance between the basecomponents to increase or decrease.

As used herein, the terms “first position,” “second position,” and“third position” are used to merely refer to dissimilar positions andare not meant to imply that all embodiments of the expandable frame canonly be adjusted to one, two, or three positions. In some embodiments,the expandable frame is adjustable to a finite number of position. Inother embodiments, the distance between one or more base components canbe increased or decreased to any desired extent, thereby allowing theexpandable frame to adjust to an almost infinite number of positions.

In some embodiments, the expandable frame has a major plane. In furtherembodiments, the base components of the expandable frame are moveablealong the connector in the major plane or a plane parallel to the majorplane.

In some embodiments, the expandable frame includes at least one pair ofbase components and at least one connector. Each pair includes a firstbase component, a second base component, at least one connectorextending from the first base component, and at least one connectorextending from the second base component. The connector extending fromeach first base component is in movable relation to each second basecomponent and such relative movement causes movement of the first basecomponent relative to the second base component. In some embodiments,the connector extending from the second base component is in moveablerelation to another base component. In further embodiments, the movementof one connector relative to a base component is independent of movementof another connector relative to another base component of theexpandable frame.

The connector extends between two or more base components and are inmoveable relation to at least one base component. Examples of connectorsinclude ratchet arms, hinges, screws, gears (e.g., worm gears),tongue-and-groove connectors, slots, pins, telescoping tubes, or similarconnecting devices. Optionally, the expandable frame includes one ormore connectors (e.g., ratchet arms) that are arcuate or curved. In someembodiments, arcuate connectors cause the expandable frame to have asubstantially circular or elliptical shape during movement from oneposition to another (e.g., from a first position to a second position).In other embodiments, the expandable frame includes one or moreconnectors (e.g., ratchet arms) that are straight.

In some embodiments, the expandable frame includes one or moremechanisms for fixing the position of one base component relative toanother base component. For example, if the expandable frame has aconnector that includes a ratchet arm, one base component may be fixedin position relative to another base component by, for example, a seriesof interlocking teeth or grooves. In another example, if the expandableframe has a connector that includes a hinge or the like, one basecomponent may be fixed in position relative to another base component bya lever which engages a series of teeth on the hinge, thereby preventingthe hinge from rotating. Other exemplary mechanisms for fixing theposition of one base component relative to another base component mayinclude hooks, levers, latches, screws, locking mechanisms, combinationsthereof, and the like. Additionally, one base component may be fixed inposition relative to another base component by, for example, anautomated mechanism, such as one or more motorized screws.

Optionally, the expandable frame may include one or more features thatfacilitate the support of one or more surgical instruments. Examples ofsurgical instruments include a light source (e.g., a surgical light), asuction device (e.g., a suction tube), a tissue cutting and evacuationinstrument (e.g., a device for cutting and removing disk material, suchas a pituitary, or a device for cutting and removing bone material, suchas a ronguer), or other surgical instruments known in the art.

In some embodiments, at least two retractor blades are attached to theexpandable frame. Each retractor blade has an inner face, an outer face,and a major axis running the length of the blade from a proximal end toan opposite distal end. In further embodiments, the outer and/or innerface of one or more of the retractor blades is arcuate in shape.

In some embodiments, the inner face of the retractor blades define aconduit when the expandable frame is at one or more positions. Infurther embodiments, the conduit is substantially cylindrical orsubstantially elliptical. Optionally, one or more retractor bladescontact each other when the expandable frame is at one or morepositions. In still more embodiments, at least some portion of theretractor blades (e.g., the distal ends of one or more blades) provide asurgical site when the expandable frame is at one or more positions(e.g., when the expandable frame is partially or fully expanded). In yetmore embodiments, at least some portion of the retractor blades (e.g.,the distal ends of one or more blades) provide a surgical site when theexpandable frame is fully expanded.

In some embodiments, the outer faces of two or more retractor bladesform a thin or relatively narrow blade, which can be useful forinserting the retractor between tissue (e.g., between muscle tissue),when the expandable frame is in at least one position. In furtherembodiments, the outer faces of two or more retractor blades define athin or relatively narrow blade while the inner faces define a conduitwhen the expandable frame is in at least one position.

In some embodiments, the proximal ends of the retractor blades areconnected to the expandable frame via a connector. Examples of suitableconnectors include clips, hinges, rivets, adhesives, tressits, or thelike. In further embodiments, the retractor blade is attached to, andextends from, a base component.

In some embodiments, a retractor blade may be attached to the expandableframe at an angle to the expandable frame (e.g., ˜90°, an angle greaterthan 90°, or an angle lesser than 90°). In further embodiments, theangle at which a retractor blade is attached to an expandable frame maybe adjusted.

In some embodiments, one continuous portion of material forms both abase component and one or more additional portions of the retractor(e.g., one or more retractor blades or connectors). For example, a basecomponent and a ratchet arm can be formed from one continuous piece ofplastic or metal, thereby reducing the number of pins or otherattachment devices needed to attach a ratchet arm to a base component.Examples of suitable materials of construction for the various portionsof the retractors of this invention include metals and metal alloys(e.g., stainless steel, aluminum, titanium, nitinol, cobalt chrome,etc.) and/or plastics (e.g., carbon fiber reinforced polymer (CFRP),ultra-high molecular weight polyethylene (UHMWPE), ultem, radel, vectra,polycarbonate, etc.)

In some embodiments, at least one blade is orientated so that the majoraxis of the blade intersects the major plane of the expandable frame ata non-normal angle. In further embodiments, at least one blade isadjustably connected to the expandable frame so that the angle at whichthe major axis intersects the major plane can be varied to a desiredextent. In still further embodiments, the blade is fixable so as to fixthe intersection at a desired angle.

In still more embodiments, at least one blade is rotatable about themajor axis of the blade. In a further embodiment, the blade is fixableat a point of rotation about the major axis.

In some embodiments, the base components are arranged to define or forman access portal that provides an opening or window with an innerdiameter that allows access to a surgical site when the expandable frameis in at least one position. Upon movement of the expandable frame froma first position to a second position, an inner diameter of the accessportal increases or decreases. In some embodiments, the expandable framecan be positioned in a relatively contracted position, thereby reducingthe inner diameter and the size of an incision needed to insert theretractor into a mammal. In further embodiments, an average diameter ofthe access portal is approximately equal to an average diameter betweentwo base components when the expandable frame is in at least oneposition. In still further embodiments, the access portal is contiguouswith a conduit formed by retractor blades when the expandable frame isin at least one position.

In some embodiments, one or more of the blades may include features thatfacilitate the support of surgical instruments. For example, a surgicalinstrument (e.g., one or more of the instruments described herein) canbe attached along a channel or tract that extends for at least someportion of the length of the blade and is used to guide or position thesurgical instrument in or near a surgical site.

FIGS. 1 and 2 illustrate two views of a portion of one embodiment of aretractor of the invention. Portion 100 includes base component 102 withattached clip blade 104. Base portion 102 includes portions of aconnector that comprises ratchet arm 106 and accommodating hole 108.Portion 100 also includes parts of a mechanism for fixing the positionof a first base component relative to a second base component thatcomprises ratchet release button 110. Ratchet release button 110 andratchet arm 106 are secured to base component 102 via an attachmentmechanism comprising pins 112, 114, respectively. Base component 102includes an attachment point for supporting surgical instruments thatcomprises attachment hole 116. Retractor blade 104 has major axis 118running from proximal end 120 to opposite distal end 122. Retractorblade 104 includes a blade attachment mechanism that comprises clip 124that connects proximal end 120 to base component 102. Both the inner andouter face of blade 104 are arcuate along axis 118.

FIG. 2 illustrates partially disassembled portion 100 from an angledissimilar to that shown in FIG. 1. Clip 124 slides into receptor 126,thereby attaching proximal end 120 of blade 104 to base component 102.Pin 112 is inserted into base 102, via pin hole 128, and passes throughchannel 130 of ratchet release button 110, thereby securing ratchetrelease button 110 to base component 102. The view shown in FIG. 2illustrates teeth 132 running along a portion of the inside length ofratchet arm 106.

In some embodiments, the connector includes a ratchet arm. For example,a ratchet arm attached to a first base component extends through anaccommodating hole in another base component, thereby attaching thefirst and second base components. The second base component can moverelative to the ratchet arm, and also move relative to the first basecomponent, by sliding up or down the length of the ratchet arm. Thefixing mechanism fixes the position of the ratchet arm at the secondbase component, thereby immobilizing the first and second basecomponents relative to each other.

FIGS. 3-5 illustrate various portions of first base component 300,second base component 500, and a mechanism for fixing the position of afirst base component relative to a second base component. FIG. 3illustrates first base component 300 that includes ratchet arm 302,accommodation hole 304, receptor 306, and void 308 which accommodatesratchet release button 400 (illustrated in FIG. 4). Ratchet releasebutton 400 includes teeth 402 and channel 404. FIG. 5 illustrates secondbase component 500 that includes ratchet arm 502, accommodation hole504, receptor 506, and teeth 508 on ratchet arm 502. The mechanism forfixing a first base component relative to a second base componentcomprises teeth 402 and teeth 508, which are complementary to oneanother. To connect first base component 300 to second base component500, ratchet arm 502 is directed through accommodation hole 304.

FIG. 4 illustrates ratchet release button 400 of first base component300. Teeth 402 of ratchet release button 400 are complementary to teeth508. Teeth 402 and/or teeth 508 can be orientated in such a way thatfirst base component 300 can move down the length of ratchet arm 502without engaging teeth 402 with teeth 508 when that movement placesfirst base component 300 relatively further from second base component500. That is, teeth 402 and teeth 505 are orientated such that movementwhich distances first base component 300 from second base component 500is relatively unhindered. However, teeth 508 and teeth 402 engage if therelative movement would decrease the distance between first basecomponent 300 and second base component 500. Relative movement of firstbase component 300 towards second base component 500 is accomplished bypressing ratchet release button 400 to disengage teeth 402 fromcomplementary teeth 508. Once teeth 402 are disengaged from teeth 508,first base component 300 can be moved closer to second base component500 and to a desired relative position. In some embodiments, the teethof a ratchet release button and/or the teeth of a ratchet arm areorientated in such a way that they engage, thereby impeding relativemovement of one base component away from another. In a furtherembodiment, the teeth are orientated to impede the relative movement ofone base component away from another base component and impede therelative movement of one base component towards another.

FIGS. 6-8 illustrates one embodiment of a retractor of the invention inthree different positions or degrees of expansion. FIG. 6 illustratesretractor 700 in a fully collapsed or contracted position. Retractor 700includes four retractor blades 702, 704, 706, 708 and an expandableframe 710 having a major plane (parallel to plane XY). Retractor blades702, 704, 706, 708 are attached at their respective proximal ends toexpandable frame 710. Retractor blades 702, 704, 706, 708 are arcuate orcurved, and in this first position, their collective inner facescontact, thereby defining a conduit in the shape of a hollow cylinder.

In the contracted position illustrated in FIG. 6, the inner diameter ofaccess portal 712, defined by base components 714, 716, 718, 720 ofexpandable frame 710, is reduced in size relative to its size in thepositions illustrated in FIGS. 7 and 8. This allows retractor 700 to beinserted into an organism or surgical patient (e.g., a human or othermammal) through an incision of minimal size. Retractor 700 includes fourratchet arms 722, 724, 726, 728 and mechanisms for fixing the positionof one base component relative to another base component that includeratchet release buttons 730, 732, 734, 736.

Retractor 700 is bisected by at least two planes that are substantiallynormal to the major plane. A first plane is parallel to the XZ plane andbisects retractor 700, running approximately between base components 714and 716 and between base components 718 and 720. A second plane isparallel to the YZ plane and bisects retractor 700, runningapproximately between base components 714 and 720 and between basecomponents 716 and 718.

FIG. 7 illustrates retractor 700 in a partially expanded, or partiallytranslated, position. To expand retractor 700 from the positionillustrated in FIG. 6 to the position illustrated in FIG. 7, force isapplied to expandable frame 710 to move base component 714 along ratchetarm 722 and base component 718 along ratchet arm 726. In this manner,expandable frame 710 moves approximately in, or parallel to, the majorplane from a first position (i.e., the one illustrated in FIG. 6) to asecond position (i.e., the one illustrated in FIG. 7) substantiallyalong the first plane and generally away from the second plane.

Ratchet arms 722, 724, 726, 728 are arcuate. Movement of base components714, 716, 718, 720 along arcuate ratchet arms 722, 724, 726, 728 causesan asymmetric or uneven expansion and contraction of retractor 700. Thatis, as expandable frame 710 expands, an average distance between theends of ratchet blades 702, 704, 706, 708 that are distal fromexpandable frame 710 increases more than the average distance betweenthe ends proximal to expandable frame 710 and more than an averagedistance between base components 714, 716, 718, 720. When used during asurgical procedure, this unequal expansion allows the distal ends of theretractor blades to retract deep tissue while reducing the size of anincision needed to accommodate the expandable frame. In someembodiments, movement of the base components does not cause anasymmetric or uneven expansion and contraction of the retractor. Forexample, if the ratchet arms are straight, expansion and contraction ofthe expandable frame results in an equal amount of expansion andcontraction of the distal ends of the blades. In some embodiments, theshape of the ratchet arms is chosen in order to produce a desired degreeof asymmetric expansion.

The curvature of ratchet arms 722, 724, 726, 728 causes base components714, 716, 718, 720 to move slightly out of the major plane as expandableframe 710 is moved to various positions or degrees of expansion andcontraction.

In some embodiments (e.g., the one shown in FIG. 6), the base componentsare arranged in such a way that the expandable frame is substantiallycoplanar and arranged flat in the major plane. However, this inventionalso includes embodiments where one or more portions of the expandableframe is not substantially coplanar at one or more positions or degreesof expansion and contraction.

FIG. 8 illustrates retractor 700 in a position where expandable frame710 is further expanded from the position illustrated in FIG. 7. Toexpand retractor 700 from the position illustrated in FIG. 7 to theposition illustrated in FIG. 8, force is applied to expandable frame 710to move base component 716 along ratchet arm 724 and base component 720along ratchet arm 728, substantially along the major plane. In thismanner, expandable frame 710 moves from the second position (i.e., theone shown in FIG. 7) to a third position (i.e., the one shown in FIG. 8)substantially along the second plane and generally away from the firstplane.

If desired, expandable frame 710 is able to be expanded or contracted tomany different positions by moving one or more of base components 714,716, 718, 720 along ratchet arms 722, 724, 726, 728, respectively. Inthis way, retractor 700 can be expanded or contracted to a wide varietyof desired positions.

Retractor 700 illustrates a connector that includes ratchet arms 722,724, 726, 728. For example, FIG. 7 illustrates ratchet arm 726 of basecomponent 716 partially extending through neighboring base component718. Similarly, ratchet arms 724, 722, and 728 extend through orpartially through base components 716, 714, and 720, respectively. Inthis manner, the connectors connect base components 714, 716, 718, 720and form expandable frame 710.

Retractor 700 also illustrates a mechanism for fixing the position of afirst base component relative to a second base component. For example,FIG. 7 illustrates ratchet release button 734, which includes a seriesof teeth or grooves that engage a second series of complementary teethor grooves on ratchet arm 726, thereby fixing the position of basecomponent 718 relative to ratchet arm 726. Hence, ratchet release button734 fixes the position of base component 716 (i.e., the “first basecomponent”) relative to base component 718 (i.e. the “second basecomponent”). Pressing ratchet release button 734 disengages thecomplementary teeth, and allows base component 718 to move along ratchetarm 726 and provides for the movement of base component 718 relative tobase component 716. Similarly, the position of base component 716relative to base component 714 is adjustable by engaging or disengagingratchet release button 732, the position of base component 714 relativeto base component 720 is adjustable by engaging or disengaging ratchetrelease button 730, and the position of base component 720 relative tobase component 718 is adjustable by engaging or disengaging ratchetrelease button 736.

To adjust retractor 700 from the position illustrated in FIG. 8 to theposition illustrated in FIG. 7, ratchet release buttons 736 and 732 arepressed, thereby allowing expandable frame 710 to move along the secondplane and generally towards the first plane. Similarly, ratchet releasebuttons 734 and 730 are used to adjust expandable frame 710 along thefirst plane and generally towards the second plane. In this manner,expandable frame 710 can be adjusted to one or more different positions,allowing retractor 700 to be expanded or contracted to a desired extent.

In some embodiments, the expandable frame includes a connector thatcomprises one or more hinges which attach two or more base components.FIGS. 9-12 illustrate four different views of retractor 900. Retractor900 includes retractor blades 902, 904, 906, 908 which are attached toexpandable frame 910. Expandable frame 910 includes base components 912,914, 916, 918. Each base component 912, 914, 916, 918 is constructed orformed from a continuous piece of material that includes each retractorblade 902, 904, 906, 908, respectively. Expandable frame 910 includesratchet arms 920, 922, which are attached to base components 918, 916,respectively. Ratchet arms 920 extends from base component 918 into theaccommodating hole of base component 912, thereby connecting basecomponent 918 to base component 912. Similarly, ratchet arm 922 connectsbase component 916 to base component 914. Retractor 900 includesmechanisms for fixing the position of a first base component relative toa second base component that comprise ratchet release levers 924, 926.Ratchet release levers 924, 926 provides the same function as theratchet release buttons illustrated previously and are used to releasethe positions of base component 914 relative to ratchet arm 922 and basecomponent 912 relative to ratchet arm 920, respectively.

Expandable frame 910 also includes a connector that comprise hinges 927,928. Hinge 927 rotatably connects base component 912 to base component914 and hinge 928 rotatably connects base component 916 to basecomponent 918. Retractor 900 also includes mechanisms for fixing theposition of a first base component relative to a second base componentthat comprises levers 930, 932. Lever 930 locks or immobilizes therotation of hinge 927, thereby fixing the position of base component 912relative to base component 914. Lever 932 locks or immobilizes therotation of hinge 928, thereby fixing the position of base component 918relative to base component 916. Expandable frame 910 defines accessportal 934.

FIG. 10 illustrates a top-down view of retractor 900 after expandableframe 910 has been moved from the first position, illustrated in FIG. 9,to a second position. Ratchet arms 920, 922 are substantially straightand provide for movement of base component 912 relative to 918 andmovement of base component 914 relative to base component 916. Ratchetlever 926 engages teeth 936 on the side of ratchet arm 920, therebyfixing the position of base component 918 relative to base component912. Similarly, ratchet lever 924 engages teeth 938 on the side ofratchet arm 922, thereby fixing the position of base component 916relative to base component 914.

FIG. 11 illustrates a side view of retractor 900 after expandable frame910 has been moved from the second position to a third position byrotating about hinge 927 and hinge 928 (not shown in FIG. 11). Hinges927, 928 provide for movement of base components 914, 916 relative tobase components 912, 918. The rotation results in an average distancebetween distal ends of retractor blades 902, 904 that is larger thanboth the average distance between the two proximal ends of retractorblades 902, 904 and the average distance between the two base components912, 914. FIG. 12 illustrates an additional view of retractor 900 afterexpandable frame 910 has been moved to the third position.

Optionally, one or more blades of a retractor include one or more bladeextensions that are telescopically and slidably attached to the blade.In some embodiments, the retractor includes a blade extension fixationmechanism that, when engaged, immobilizes or secures the blade extensionat a desired telescoped length. One example of a blade extensionfixation mechanism is one or more series of teeth or ridges on the bladeand/or blade extension which slidably secure the extension to the blade.Another example of a blade extension fixation mechanism includes aseries of teeth on the blade and a tab on the blade extension. The tabengages the teeth on the blade to immobilize the blade extension.Applying force to the tab disengages it from the teeth and allows theblade extension to slide relative to the blade. Many other bladeextension fixation mechanisms are encompassed by this invention, such ashooks, levers, latches, screws, locking mechanism, combinations thereof,and the like. Additionally, the blade extension fixation mechanisms caninclude an automated mechanism, such as one or more motorized screws.

Optionally, a retractor includes a mechanism for preventing the bladeextension from disengaging from a blade as it moves relative to theblade. An example of such a mechanism include one or more grooves ortracts on the blade and/or blade extension which slidably secure theextension to the blade. The grooves allow the extension to sliderelative to the blade, but prevent the extension from disengaging fromthe blade. Many other mechanisms for preventing the blade extension fromdisengaging from a blade are encompassed by this invention.

Optionally, the blade extension includes a telescope tab which providesa telescopic attachment point to ease the act of telescoping the bladeextension.

The inner face of blade 1300 is illustrated in FIGS. 13A, 13B, and 13C,with blade extension 1302 extending from distal end 1304 of blade 1300at progressively longer telescopic lengths. Blade 1300 includes anattachment mechanism that comprises clip 1306 at proximal end 1308.Blade 1300 includes blade extension fixation mechanism comprising twoseries of teeth 1310 which extend at least a portion of the length ofblade extension 1302. A complementary series of teeth forcibly engageboth tracts of teeth 1310, keeping blade extension 1302 at a desiredtelescopic length. Blade extension 1302 includes telescopic attachmentpoint 1312 which protrudes through an opening in the inner face of blade1300.

Optionally, one or more blades and/or blade extensions include a toe-outprotrusion extending from the distal end of the outer face. FIG. 14illustrates a close up view of distal end 1314 of the outer face ofblade extension 1302. Toe-out protrusion 1314 extends from the outerface of blade extension 1302. Toe-out protrusion 1314 allows bladeextension 1302 to more effectively retract tissue from a surgical sitecompared to a similar blade extension lacking a toe-out protrusion.Blade extension 1302 also includes ridges 1316 which extend at least aportion of the length of blade extension 1302, and provide moreeffective retraction of tissue from a surgical site compared to asimilar blade extension lacking ridges. In further embodiments, thetoe-out protrusion extends at an angle from the face of the blade orblade extension at an angle (e.g., a right angle or an angle greater orlesser than 90°).

In some embodiments, the outer face of one or more blade and/or bladeextensions include a textured surface to assist the blades or extensionsin gripping tissue. This provides for improved retraction of tissue at asurgical site. For example, portions of the outer faces can have a roughtexture, ridges (e.g., the ridges shown in FIG. 14), or similar surfacetextures.

FIG. 15 illustrates an embodiments of a retractor of the invention thatincludes blade extensions. Retractor 1500 includes expandable frame 1502in a fully expanded position with the greatest average distance betweenbase components 1504, 1506, 1508, 1510. Blades 1512, 1514, 1516, 1518includes blade extensions 1520, 1522, 1524, 1526, respectively. FIG. 15illustrates expandable frame 1502 at an expanded position without theblade extensions 1520, 1522, 1524, 1526 telescoped from blades 1512,1514, 1516, 1518, respectively.

FIG. 16A illustrates another embodiment of the invention that includesretractor 1600. Retractor 1600 includes expandable frame 1602 (which isat a slightly less expanded position than expandable frame 1502illustrated in FIG. 15) and blade extensions 1620, 1622, 1624, and 1626partially telescoped from blades 1612, 1614, 1616, and 1618,respectively. Retractor 1600 also comprises a plurality or connectorsthat include arms 1638, 1640, 1642, and 1644.

FIG. 16B illustrates retractor 1600 with expandable frame 1602 in acontracted or condensed position and extensions 1620, 1622, 1624, and1626 partially telescoped from blades 1612, 1614, 1616, and 1618.Retractor 1600 includes a plurality of universal attachment points,including attachment points or holes 1630, 1632, 1634, and 1636.Attachment holes 1630, 1632, 1634, and 1636 can be used to attachsurgical instruments, additional blades, retractor support structures(e.g., rigid arms), and the like.

FIG. 16C illustrates one perspective view of a portion of retractor 1600that includes component 1608, extension 1624, and arm 1644. FIG. 16Dillustrates another perspective view of a portion of retractor 1600 thatincludes component 1608 and extension 1624.

FIG. 16E illustrates yet another perspective view of a portion ofretractor 1600 that includes component 1608, blade 1616, and arm 1644.In the perspective view shown in FIG. 16E, extension 1624 has beenremoved from blade 1616.

FIG. 16F illustrates a perspective view of a portion of retractor 1600that includes a disassembled view of the portion of retractor 1600 thatis illustrated in FIG. 16E. Ratchet arm release button 1662 is assembledto base component 1608 by using pin 1656. Spring 1652 providessufficient force to engage arm 1642 (not illustrated in FIG. 16F) andfrustrate movement of component 1608 relative to arm 1642, unless apractitioner depresses button 1662. Retractor 1600 is free to expandwithout pressing the buttons due to the ramping of the complementaryteeth on the arms and buttons. To collapse or contract retractor 1600,the practitioner of the invention presses the buttons to disengage theteeth of the arms and buttons. Arm 1644 is secured to base component1608 with pin 1654. Ratchet arm 1644 includes a portion of a mechanismfor securing the relative position of base component 1608 that includesteeth 1650.

In some embodiments, the connectors of the retractors of this inventionserve as attachment points for additional surgical instruments and/orretractor blades. FIG. 16G illustrates another perspective viewretractor 1600 that includes blade 1670. Trapezoidal blade 1670 isattached or assembled to arm 1642. Handle 1672 is used to assemble blade1670 to retractor 1600. A practitioner of the invention can use arm 1672to assemble blade 1670 to retractor 1600 at attachment point 1632 (notillustrated in FIG. 16G).

While blade 1670 comprises an trapezoidal shape, it will be recognizedthat the blades of the retractors of the invention can comprise a formor a shape of blades known in the art. FIGS. 16H and 16I illustrate twoalternative blades 1672 and 1674 which are attached or assembled to arms1676 and 1678, respectively.

In some embodiments, an inserter is use to direct the retractors of thepresent invention to a desired location. FIG. 16J illustrates a portionof the invention that includes inserter 1680. Inserter 1680 includes aplurality of attachment pins 1682. Attachment pins 1682 secure inserter1680 to some or all of the attachment holes of the frame of theretractor of the invention. A practitioner of the invention assembles orattaches inserter 1680 to a retractor of the invention and uses handles1684 to position or direct retractor 1600 to a desired location within amammalian anatomy.

FIGS. 16K and 16L illustrate perspective view of telescoping bladeextender 1886. Telescoping blade extender 1886 includes distal end 1888and proximal ends 1890. A practitioner uses proximal ends 1890 to slideblade extension(s) 1620, 1622, 1624, and/or 1626 with respect to blades1612, 1614, 1616, and 1618 to a desired location within a mammaliananatomy, respectively.

FIG. 16M illustrates a perspective view of telescoping blade remover1892. Telescoping blade remover 1892 includes distal end 1896 andproximal ends 1894. A practitioner uses proximal ends 1894 to latch ontoa blade extension and disengage it from a mammalian anatomy and/orreposition the extension to a desired location within a mammaliananatomy.

The blades and blade extensions of this invention can be any size orshape desired. In some embodiments, one or more blades or bladeextensions are shaped and/or sized for a specific task. For example, ablade can be shaped to retract muscle tissue, adipose tissue, nervetissue, or other types of tissue. Examples of various blade withdisparate trapezoidal shapes are illustrated in FIGS. 17A-17C. Theblades illustrated in FIG. 17A-17C are just a few examples oftrapezoidal geometries and this invention includes a wide rangedifferent blade shapes (e.g., blades with non-trapezoidal geometries).

Optionally, the retractors of this invention include additionalextensions at the distal ends of the blades or blade extensions. FIG.17D illustrate the distal end of blade 1700, which includes pivotingextension 1702 that rotates about hinge 1704. FIGS. 17E and 17Fillustrate another embodiment of an additional blade extension. Distalend of blade 1750 are slidably attached to two additional extensions1752 by slides 1754. Optionally, additional extensions are fixable intoa desired position.

Optionally, one or more surgical instruments are attached to theretractor to provide additional utility. Examples of such surgicalinstruments include surgical lighting source, a portion of a source forproducing suction, or other surgical instruments that are known in theart. In some embodiments, surgical instruments are attached to anexpandable frame with a mechanism for supporting surgical instruments.The surgical instruments can be attached prior to, at some intermediatestate of, or after the expansion of the retractor. In some embodiments,the inner or outer face of the blades or blade extensions includelongitudinal grooves or tracts which can be used to slide or otherwiseguide surgical instruments down the length of the blades or bladeextensions and into or near a surgical site.

FIG. 18 illustrates retractor 1800, which includes expandable frame1802. Expandable frame 1802 includes base components 1804, 1806, 1808,1810. Base components 1804, 1806, 1810 define attachment holes 1812,1814, 1816, respectively. Light source 1818 is attached to basecomponent 1808 with a mechanism for supporting surgical instruments thatcomprises instrument clip 1820 at an attachment hole on base component1808.

FIG. 19 illustrates retractor 1900 which includes expandable frame 1902.Expandable frame includes base components 1904, 1906, 1908, 1910. Basecomponents 904, 1906, 1908, 1910 define attachment hole 1912. Attachmenthole 1912 provides an attachment site for instrument clips 1914, 1916.Instrument clips 1914, 1916 secure instruments, such as surgicallighting source 1918, to the expandable frame.

In some embodiments, extra blades are attached to the retractor toprovide additional utility. FIG. 20 illustrates attachment of additionalblades to retractor 2000, which includes base components 2002, 2004.Base components 2002, 2004 are attached to expandable frame 2006 alongexposed ratchet arms, such as ratchet arm 2008. Base component 2004includes blade 2010 and ratchet release buttons 2012. Ratchet releasebuttons 2012 secure base component 2004 at a relative position toratchet arm 2008.

FIGS. 21A-21D illustrates retractor 4000 which is yet another embodimentof a retractor of the invention. FIG. 21A illustrates retractor 4000 ina first position in which the retractor is fully collapsed or contractedposition. FIG. 21B illustrates retractor 4000 in a second position inwhich the retractor has been expanded or opened. FIG. 21C illustratesanother view of retractor 4000 in the second position. FIG. 21Dillustrates a bottom view of retractor 4000 in the second position.

Retractor 4000 includes expandable frame 4010 having a major planeparallel to the XY plane. Expandable frame 4010 comprises a first basecomponent 4014, a second base component 4016, a third base component4018, and a fourth base component 4020. While retractor 4000 isillustrated in FIGS. 21A-21D as having four base components, in otherembodiments, the retractor comprises two, three, or more than four basecomponents. Optionally, retractor 4000 includes at least one mechanismfor supporting surgical instruments (not illustrated in FIGS. 21A-21D).Examples of suitable mechanisms for supporting surgical instrumentsinclude those that are described herein, such as instrument clipssimilar to that illustrated in relation to FIGS. 1, 2, and 18, orattachment grooves.

Base components 4014, 4016, 4018, 4020 are connected to one anotherusing connectors that include two rods 4022, 4024. Rod 4022 connectsfirst base component 4014, second base component 4016 and fourth basecomponent 4020, and rod 4024 connects second base component 4016, thirdbase component 4018, and fourth base component 4020. Rods 4022 and 4024extend completely through first base component 4014 and third basecomponent 4018, respectively. In the position illustrated in FIG. 21A,rods 4022 and 4024 also extend completely through second base component4016 and third base component 4020, respectively. Base components 4016and 4020 can translate along a length of rods 4022 and 4024. Basecomponent 4014 can translate along a length of rod 4022 and basecomponent 4018 can translate along a length of rod 4024.

The retractor also includes one or more mechanisms for fixing theposition of one base component (not illustrated in FIGS. 21A-21D)relative to another base component. Examples of suitable mechanisms forfixing the position of one base component relative to another basecomponent are described herein, and include the mechanisms for fixingthe position of one base component relative to another base componentthat are illustrated in FIGS. 1-3, 6-8, and 9-12, as well as otherratchet, screw, or retaining mechanisms.

Retractor 4000 includes retractor blades 4002, 4004, 4006, and 4008,which are attached to base components 4016, 4018, 4014, and 4020,respectively. Retractor blades 4002, 4004, 4006, 4008 are arcuate orcurved, and in the first position illustrated in FIG. 21A, theircollective inner faces contact, thereby defining a conduit in the shapeof a hollow circular cylinder having a smooth or substantially seamlessprofile. In some embodiments, the conduit can be an elliptical cylinder.

In some embodiments, at least a portion of retractor 4000 includes aradiolucent material. For example, a portion of the retractor caninclude radiolucent plastics, aluminum, thin stainless steel, titanium,nitinol, or cobalt chrome.

Optionally, the retractor blades can include integral sleeve inserts.For example, a retractor blade can include a blade extension that istelescopically and slidably attached to a retractor blade. The retractorcan also include a blade extension fixation mechanisms that, whenengaged, immobilizes a blade extension relative to the remainder of theretractor blade. Examples of blade extensions and fixation mechanismsare described herein, such as in relation to FIGS. 13A-13C, 16, and17D-17F.

In some embodiments, one or more of the retractor blades has a toe-outprotrusion which allows the blades to grip tissue and provides forbetter retraction of tissue. Examples of such a toe-out protrusion aredescribed herein, such as in relation to FIG. 14.

The major axis of retractor blades 4002, 4004, 4006, 4008 are normal tothe major plane of the expandable frame. In some embodiments, one ormore of the blades are attached to the expandable frame such that theblade is rotatable about the major axis of the blade and fixable at adesired point of rotation about the major axis. For example, a blade canbe attached to the base component with a vertical hinge that allows theblade to be rotated from side to side. In other embodiments, one or moreof the blades are attached to the expandable frame in such a way thatthe blade is rotatable about an axis that is parallel to the major planeof the expandable frame. For example, a blade can be attached to thebase component with a horizontal hinge that allows the blade to berotated up and down.

Retractor 4000 is bisected by at least two planes that are substantiallynormal to the major plane XY. A first plane is parallel to the XZ planeand bisects retractor 4000, running approximately between basecomponents 4014 and 4018 and bisects base components 4016 and 4020. Asecond plane is parallel to the YZ plane and bisects retractor 4000,running approximately between base components 4016 and 4020 and bisectsbase components 4014 and 4018.

In the contracted position illustrated in FIG. 21A, the inner diameterof access portal 4012, defined by base components 4014, 4016, 4018, 4020of expandable frame 4010, is reduced in size relative to its size in thepositions illustrated in FIGS. 21B-21D. This allows retractor 4000 to beinserted into an organism or surgical patient (e.g., a human or othermammal) through an incision of minimal size.

Once retractor 4000 has been inserted into the desired anatomicallocation, retractor 4000 can be expanded or deployed. For example, aspreader instrument (such as the one described in relation to FIGS.26-28) can be used to open the distal ends of the retractor blades.Retractor 4000 can be used to retract and hold muscle at an angle thatis about perpendicular to the greatest muscle force, thereby allowingfor better or optimal placement of retractor blades due to anatomicalconstraints and reducing the problems associated with tissue creep whichare caused by muscle and other tissue not being restrained from theworking channel.

FIG. 21B illustrates retractor 4000 in a partially expanded, orpartially translated, position. To expand retractor 4000 from theposition illustrated in FIG. 21A to the position illustrated in FIG.21B, force is applied to expandable frame 4010 to move base component4016 along rod 4022 and relative to base component 4020 and rod 4024. Astop (not shown) located at the ends of rods 4022 and 4024 preventsattached components from translating off of the ends and disengaging therods. Base components 4014 and 4018 can be slideably positioned at adesired position along rods 4022 or 4024, respectively. In this manner,expandable frame 4010 moves approximately in, or parallel to, the majorplane from a first position (i.e., the one illustrated in FIG. 21A) to asecond position (i.e., the one illustrated in FIG. 21B) substantiallyalong the first plane and generally away from the second plane.Optionally, additional base components with or without retractor bladescan be secured to rods 4022, 4024.

If desired, expandable frame 4010 is able to be expanded or contractedto many different positions by moving one or more of base components4014, 4016, 4018, 4020 along one of rods 4022, 4024. In this way,retractor 4000 can be expanded or contracted to a wide variety ofdesired positions.

Rods 4022, 4024, as shown, are straight, so movement of the basecomponents does not cause an asymmetric or uneven expansion andcontraction of the retractor. In other words, expansion and contractionof the expandable frame results in an equal amount of expansion andcontraction of the distal ends of the blades and the base componentsremain coplanar with one another or arranged flat in the major plane XY.

In other embodiments, the shape of the rods or other connector is chosenin order to produce a desired degree of asymmetric or curved expansionsuch that the expandable frame defines an access portal having anaverage diameter that is smaller than the greatest distance between thedistal ends of any two blades when the expandable frame is in the secondposition. In some embodiments, one or more portions of the expandableframe are not substantially coplanar at one or more positions or degreesof expansion and contraction.

In some embodiments, the blades and/or blade extensions add additionalstructural rigidity to the expandable frame when the expandable frame isat one or more positions. For example, interlocking blades or bladeextensions can be mechanically connected to one another along someportion of their edges or sides, thereby providing additional structuralrigidity.

The retractors of this invention can be constructed of many differenttypes of material, including a wide range of polymers, metals (e.g.,titanium), and metal alloys (e.g., stainless steel, cobalt chrome, andtitanium alloys). Some portions of the retractor may require a strong,rigid material (e.g., the bases, ratchet arms, and hinges of theexpandable frame). Other portions of the retractor may require aflexible, durable material in order to withstand repeated distortions(e.g., a flexible tab of a fixing mechanism). Preferably, the materialsof construction are biocompatible.

Additionally, the materials of construction can be chosen to providefavorable characteristics or lend additional advantages during someportion of the surgical process. For example, it is often necessary totake X-ray images and/or fluorimages of a subject during surgery. Hencein some embodiments, at least a portion of the retractor is constructedof radiolucent materials. However, it can be beneficial to have areference point for a marker on an X-ray image. So in other embodiments,at least a portion of the retractor is made from a material that isradiopaque.

In some embodiments, this invention includes a method of forming asurgical site in an organism (e.g., a human or other mammal). In oneembodiment, the method comprises the steps of a) creating an incision inthe skin of a mammal; b) retracting the tissue of the mammal at theincision with a retractor of this invention to form a surgical site.

In some embodiments, the surgical site is formed at a spinal column. Infurther embodiments, the surgical site is formed during a surgicalprocedure that includes at least one member of the group consisting of atransformational lumbar interbody fusion procedure, a posterior lumbarinterbody fusion procedure, a posterolateral fusion procedure, and otherapproaches (e.g., anterior, lateral, anterior-lateral, and other areasof the spine such as, for example, cervical or thoracic areas). Theretractors of this invention are also suitable for use in nonspinalsurgical procedures.

In some embodiments, an obtruator is inserted into the incision beforethe retractor is inserted. In further embodiments, one obtruator andsubsequent dilators are inserted to dilate the incision before theretractor is inserted.

Optionally, the retractor is assembled to an insertion tube before it isinserted into the organism. An insertion tube provides for easierinsertion of a retractor into, and positioning within, an organism. Insome embodiments, the insertion tube attaches to the expandable frame ofa retractor.

In some embodiments, the retractor is inserted over an obtruator duringinsertion of the retractor to the depth of the surgical site or near thedepth of the surgical site to be formed. FIGS. 22A-22H illustrate oneembodiment of such a method used to retract tissue near the spine of ahuman. Soft tissue and some bone mass has been omitted from the figuresfor clarity.

FIG. 22A illustrates obtruator 2100 after it has been inserted into anincision and forced down to the surgical site (i.e., next to the spinalcolumn). Optionally, the obtruator is directed along a guide wire whichhas previously been tethered to the surgical site.

Once obtruator 2100 is in position at surgical site 2102, retractor 2104is assembled to insertion tube 2106. The combined assembly of retractor2104 and insertion tube 2106 defines a conduit that has an innerdiameter that is greater than the outer diameter of obtruator 2100. Thisallows the combined assembly of retractor 2104 and insertion tube 2106to, in turn, be assembled over obtruator 2100, as shown in FIG. 22B.

Once retractor 2104 is assembled over obtruator 2100, a surgeon or otherpractitioner of this embodiment pushes retractor 2104 down the length ofobtruator 2100 to surgical site 2102 by applying force on insertion tube2106, as shown in FIG. 22C. Once retractor 2104 is at surgical site2102, obtruator 2100 is removed from the incision, leaving retractor2104 in the incision and attached to insertion tube 2106, as shown inFIG. 22D.

Outer sleeve 2110 contacts the frame and is used to position retractor2104 to a desired depth and position (e.g., to the surgical site orabove the surgical site to allow sufficient room for extension of theblade extensions). Alternatively or in addition, outer sleeve 2110captures the proximal end of the blades that are inserted into thedovetail feature of the proximal end of retractor 2104. Inner sleeve2108 is used to insert blades and/or blade extensions onto the retractoror to extend one or more blade extensions to a desired extent.Alternatively or in addition, inner sleeve 2108 is used to capture thedistal end of the blade to prevent the blades from splaying wheninserted into the incision. Blades and/or blade extensions can beinserted or positioned in any desired order or combination (e.g., allblades or extensions inserted or positioned simultaneously orindividually). Inner sleeve 2108 is then removed from insertion tube2106, as shown in FIG. 22E, followed by the outer sleeve 2110, as shownin FIG. 22F.

When all the portions of the insertion tube 2106 have been disassembledfrom retractor 2104, one or more blade extensions 2112 can be extendedto a desired extent around the surgical site 2102, as shown in FIG. 22G.As shown in FIG. 22G, blade extensions 2112 are attached to the outerface of the blades of retractor 2104, however, in some embodiments, theblade extensions are attached to the inner face of the blades.

Finally, the expandable frame of retractor 2104 is moved to a desiredposition, such as the one shown in FIG. 22H. The surgical site is formedby the distal ends of the blades and/or blade extensions 2112.Optionally, the retractor is attached to a surgical retractorpositioning mechanism (e.g. one or more a rigid arms, not shown) whichrigidly secures the retractor in the desired location.

FIG. 23 illustrates one embodiment of an insertion tube. Insertion tube2200 includes attachment portion 2202, handle portion 2204, and stop2206. Attachment portion 2202 includes various attachment prongs 2208which are arranged in a pattern so as to match the top surface of anexpandable frame. Handle portion 2204 provides a convenient place for asurgeon or other practitioner of this invention to apply force to anattached retractor. Stop 2206 ensures that a hand of a practitioner willnot slip off of the handle portion 2204 as force is applied to insertand/or position an attached retractor. Stop 2206 includes lock 2210,which locks and secures one or more attachment prongs 2208 to aretractor. In some embodiments, the attachment prongs of an insertiontube provide a slight amount of resistance when secured to a retractorso the insertion tube remains attached during insertion of theretractor.

FIG. 24 illustrates another embodiment of an insertion tube. Insertiontube 2300 includes attachment portions 2302, handle portion 2304, andstop 2306, all of which serve similar functions to the analogousportions in the embodiment of FIG. 23. However, insertion tube 2300includes blade extension portion 2308, which includes one or moreextender tabs 2310, which are mechanically connected to blade extenderattachments 2312. By pushing sliding extender tabs 2310, a practitionercan lengthen blade extender attachments 2312 which are mechanicallycouple with one or more blade extensions in an attached retractor. Inthis manner, insertion tube 2300 allows a practitioner to insert aretractor, position a retractor, and/or extend one or more bladeextenders to a desired telescopic length.

In some embodiments, a retractor of the invention is assembled (e.g.,mechanically attached, or slipped or positioned over) to one or moreobtruator and dilators before insertion into an organism. FIG. 25illustrates such an assembly. Assembly 2400 includes retractor 2402, aninsertion tube 2404, an obtruator 2406, and dilators 2408 and 2410.

Once a retractor of the invention has been positioned in desiredposition relative to a surgical site, the expandable frame is moved to adesired position in order to form the surgical site. Optionally, one ormore distraction instruments are used to move the expandable frame andretract tissue from the surgical site. FIG. 26 illustrates oneembodiment of a distraction instrument. Distraction instrument 2500 hasan attachment portion 2502 and a gripping portion 2504. Applying forceto gripping portion 2504 causes attachment portion 2502 to splay orexpand. By connecting attachment portion 2502 to a retractor, theapplication of force to the gripping portion will move an expandableframe into a desired position. In some embodiments, the attachmentportion is attached to the outer diameter of the retractor, while inother embodiments it is attached to an inner diameter of the retractor(as illustrated in FIGS. 27 and 28).

In some embodiments, the expandable frame is expanded or contracted withthe use of one or more keys or screws that engage the teeth on one ormore ratchet arms and cause one or more base components to move relativeto a ratchet arm. This provides for independent adjustment or eachratchet arm to a desired position or desired extent of expansion.

FIG. 27 illustrates the attachment of distraction instrument 2600 toretractor 2602. Attachment portion 2604 attaches to an inner diameter ofaccess portal 2606 of expandable frame 2608. Squeezing gripping portion2610 together causes attachment portion 2604 to splay, as illustrated inFIG. 28, thereby moving expandable frame 2608 into a desired position.

In some embodiments, this invention includes a method of forming asurgical site in an organism. In one embodiment, the method comprisesthe steps of creating an incision in the organism and retracting thetissue of the organism at the incision with a retractor of the inventionto form a surgical site, thereby forming a surgical site defined atleast in part by the distal ends of the blades. In some embodiments, theorganism is a mammal. In further embodiments, the mammal is a human.

In some embodiments, the surgical site is formed near a spinal column.In further embodiments, a surgical site is formed during a surgicalprocedure that includes at least one member of the group consisting of atransformational lumbar interbody fusion procedure, a posterior lumbarinterbody fusion procedure, and a posterolateral fusion procedure.

In some embodiments, the incision is first dilated with at least oneobtruator before inserting the retractor. In a further embodiment, aretractor is inserted over the obtruator during insertion of theretractor to the depth of the surgical site to be formed.

Optionally, the retractor is attached to a surgical retractorpositioning mechanisms that rigidly secures the retractor in a desiredlocation. One example of a positioning mechanism is an adjustable rigidarm that attaches to a surgical table.

In some embodiments, this invention includes an assembly comprising asurgical retractor assembled to at least one obtruator. For example,this invention includes a surgical retractor which is mechanicallyattached to an obtruator. Optionally, the surgical retractor is notmechanically or rigidly attached to an obtruator, but is positioned orslid over an obtruator.

In another embodiment, this invention includes a surgical retractor,comprising an expandable frame that includes at least two basecomponents, and at least one connector that connect the base components,wherein at least one base component is moveable along the connector; andat least two retractor blades attached to the expandable frame, whereineach blade has a proximal end attached to expandable frame, a distal endopposite the proximal end, and a major axis. Upon movement of theconnector relative to at least one base component, the expandable framemoves from a first position to a second position, thereby increasing theaverage distance between two base components to a first distance andincreasing the average distance between the distal ends of two retractorblades to a second distance, wherein the first distance is less than thesecond distance.

In another embodiment, this invention includes a surgical retractor,comprising an expandable frame that includes at least two basecomponents, and at least one connector that connect the base components,wherein at least one base component is moveable along the connector; andat least two retractor blades attached to the expandable frame, whereineach blade has a proximal end attached to expandable frame, a distal endopposite the proximal end, a major axis, and an outer face. Uponmovement of the connector relative to at least one base component, theexpandable frame moves from a first position to a second position,thereby increasing the average distance between two base components. Thecombined outer faces of the retractor blade are cylindrical when theexpandable frame is in a first position.

In another embodiment, this invention includes a surgical retractor,comprising a housing component having a central axis and including acylindrical portion, wherein the cylindrical portion defines a conduithaving an inner diameter normal to the central axis; and a blade portionthat is contiguous with one end of the cylindrical portion, wherein theblade portion includes at least two blades, wherein a distal portion ofeach blade is moveable relative to the central axis; and a cylindricalexpander component having an outer diameter, wherein the outer diameteris smaller than the inner diameter of the cylindrical portion and theexpander component is movably attached to the housing component. In afirst position, distal ends of the blade portion are proximate, and uponmovement of the distal portion of the blades relative to the centralaxis, the blades move from a first position to a second position,thereby forming a continuous conduit down the length of the centralaxis. Optionally, at least one blade includes a tow-out protrusion.

FIGS. 29 and 30 illustrates one embodiment of a retractor of theinvention. FIG. 29 illustrates retractor 2800 in a first position.Retractor 2800 comprises housing component 2802 that has central axis2804. Housing component 2802 includes cylindrical portion 2806 whichdefines a conduit having inner diameter 2808 normal to central axis2804. Blade portion 2810 is contiguous with one end of cylindricalportion 2806 and includes blades 2812. Blades 2812 have distal portions2814 that is moveable relative to central axis 2804. Cylindricalexpander component 2816 is movably attached to housing component 2802 byscrew threads 2818. Cylindrical expander component 2816 includes a bladeexpansion mechanism that comprises an extension 2820 that extends downthe inner walls of cylindrical portion 2806.

FIG. 29 illustrates retractor 2800 in a first position, where distalends 2814 are proximate to one another. FIG. 30 illustrates retractor2800 after expander component 2816 has been rotated relative to housingcomponent 2802. Such rotation causes expander component 2816 to pressalong screw threads 2818, pressing extension 2820 into the inner wall ofblade portion 2810 and causing blades 2812 to move radially from centralaxis 2804, thereby expanding a surgical site.

In the first position illustrated in FIG. 29, distal ends 2814 wereproximate to each other and blade portion 2810 formed a cone. In thesecond position illustrated in FIG. 30, distal ends 2814 are splayed ordistant from each other and central axis 2804. In the first position,the conical shape of blade portion 2810 allow retractor 2800 to beeasily inserted into an organism (e.g., through an incision) with aminimum of trauma to surrounding tissue. Once in a desired location,retractor 2800 can be expanded to the second position, thereby forming asurgical site and providing a practitioner access to that site.

FIG. 31 illustrates retractor 3000, with distal ends 3002 in a firstposition. FIG. 32 illustrates retractor 3000 with distal ends 3002 in asecond position. FIG. 33 illustrates retractor 3000 with attachedexpander component 3004.

In another embodiment, this invention includes a method of performingsurgery on an organism, comprising the steps of creating an incision inthe organism, retracting the tissue surrounding the incision with aretractor to form a surgical site, and performing a surgical procedureat the surgical site.

In some embodiments, this invention includes an illuminated surgicalcannula. In one embodiment, an illuminated surgical cannula, comprises asurgical cannula that has an outer diameter, an inner diameter, a distalend, and a proximal end, wherein the inner diameter, the distal end, andthe proximal end define an interior area; and an interface ring attachedto the proximal end, wherein the interface ring includes a light sourceinterface mechanism in photonic communication with an array of fiberoptic wire, wherein the array is arranged to direct light towards thedistal end of the cannula. The interior area is illuminated by the lightsource. In some embodiments, the interface ring includes a light source(e.g., a led light or some other light source).

In some embodiments, the cannula includes at least one fiber optic wirethat is in photonic communication with the array of the interface ringat the proximal end and extends down at least a portion of the length ofthe cannula towards the distal end. In a further embodiment, at least aportion of the fiber optic wire is embedded in the cannula between theouter and inner diameters.

Optionally, at least a portion of the cannula is translucent. In someembodiments, at least a portion of the cannula is transparent. Infurther embodiments, the cannula tube incorporates features (e.g.,bevels or surface roughness) that captures and redirects light to adesired location to aid in illumination.

FIG. 34 illustrates one embodiment of an interface ring. Interface ring3300 includes a light source interface mechanism 3302. Light sourceinterface mechanism 3302 directs light from an outside light source(e.g. a light source commonly used in an operating procedure) to anarray 3304 of fiber optic wire 3306. Interface ring 3300 defines accessportal 3308 that provides a practitioner access to an attached cannula.Array 3304 is disposed around interface ring 3300 and projects lightdown the length of a cannula. Optionally, array 3304 directs light to acannula that comprises at least a portion of a light-conductingmaterial. In some embodiments, an interface ring forms a complete circleand fits on top of a cannula or retractor of the invention. In otherembodiments, an interface ring forms a portion of a circle (e.g., a halfcircle or a quarter circle) and fits on top of a cannula or retractor ofthe invention.

FIG. 35 illustrates a portion of a cannula that includes alight-conducting material. Cannula 3400 includes a plurality of fiberoptic wires 3402. Fiber optic wire 3402 are embedded within the materialforming the wall of cannula 3400. FIG. 36 illustrates interface ring3300 assembled to a portion of a cannula 3400.

The cannula illustrated in the figures is just one embodiment of acannula of the invention. The illuminated cannula, or portions thereof(e.g., an interface ring), can be used with any retractor of theinvention.

In some embodiments, this invention features methods of performingsurgical procedures on the spine of a human using retractors of thepresent invention. FIGS. 37A-37U illustrate embodiments of the inventionthat include a method of using a retractor (e.g., a retractor of theinvention) during a surgical procedure on the spine of a human andrelated instruments and tools of the invention.

FIG. 37A illustrates patient 3702 in a prone position on table 3704(e.g., a Jackson Table or other table used for image procedures) in sucha way so as to provide an unrestricted view for imaging. In someembodiments, a frame (e.g., a Wilson frame) is used to assist thepractitioner in placing patient 3702 in a desired position.Additionally, sockets (e.g., a Clark Socket) can be positioned on thetable rail lateral to the patient's mid or upper thigh, therebyfacilitating subsequent placement of a rigid arm assembly.

Proper targeting of the surgical site eases surgery and minimizes theneed to enlarge an incision. In some embodiments, the multifidus andlongisimus muscles that run parallel to the spine are dilated.Optionally, fluoroscopy is used to locate a desired level and closeattention is made to keep the targeted surgical site at the center ofthe fluoroscopic view. For example, for a transformational lumbarinterbody fusion, the center of the target is generally the medialborder of the facet joint of the desired disc level. An incisiontemplate may be used (with or without fluoroscopic guidance) to locatethe incision's center over the disc space of the proper level to beoperated on. Pressing the retractor into the skin of patient 3702 willmake an imprint and provide a good indication of the size of the neededincision.

Once the surgical site has been targeted, a longitudinal incisionslightly larger than the retractor of the invention (e.g., a retractorof the invention that is in a semi- or fully-contracted or condensedform) is made. In some embodiments, only the skin is incised sincedilators can be used to pierce and dilate the fascia.

Once the incision is made, a dilator is inserted into the incision,bluntly piercing the fascia to dilate the paravertebral muscle tissuedown to the laminar level, as illustrated in FIG. 37B. Optionally, thefascia is incised prior to the insertion of the first dilator. Thedilator's position may be confirmed fluoroscopically. With carefultactile sensation, the paravertebral muscles are swept free from thelamina, base of the spinous process, and over the facet joint with agentle wanding motion along line 3716, thereby facilitatingvisualization and ensuring the subsequent dilators and retractor isfully seated against the facet.

As shown in FIG. 37C, sequential dilation is performed by passing thenext largest dilator 3710 over dilator 3706 and directed down tosurgical site 3708. Similarly, dilator 3712 is then passed over dilator3710 and then dilator 3714 is passed over dilator 3712. In someembodiments, an introducer is utilized to insert the larger dilators.

In some embodiments, depth measurements are taken from the where theskin contacts the dilator. The depth is most effectively measures withdilators 3710 or 3712, as these dilators will be flush to the bone andproduce the most accurate measurement.

Once the incision has been dilated, a retractor of the invention isdirected to surgical site 3708. In some embodiments, the retractor isdirected to surgical site 3708 with an open Wiltse approach where thenatural muscle plane is located through a mobilized midline incision ora lateral incision.

The retractor is assembled before it is directed to surgical site 3708.FIG. 37D illustrates assembled retractor 3730. Retractor 3732 includesbase components 3734, 3736, 3738, and 3740.

FIG. 37E illustrates one step of the assembly process. Base component3740 includes arm 3742. Base component 3734 includes arm 3744 anddefines arm hole 3750. Release button 3752 is depressed to disable thelocking mechanism of component 3734, and arm 3742 is directed throughhole 3750, thereby connecting or assembling component 3740 to component3734. Similarly, component 3736 is assembled to component 3738.

Once component 3740 is assembled to component 3734 and component 3438 isassembled to component 3736, release buttons 3754 and 3756 are depressedand arm 3748 is directed through component 3740 and arm 3744 is directedthrough component 3740, thereby assembling all four base components, asshown in FIG. 37F. Retractor blade extensions 3760, 3762, 3764, and 3766are then slide into base components 3734, 3736, 3738, and 3740,respectively, as illustrated in FIG. 37G. In this manner, a practitionerof the invention assembles retractor 3730, as shown in FIG. 37D.

Optionally, the telescoping blade extensions of retractor 3730 areextended to a desired length before inserting the retractor into patient3702. FIG. 37E illustrates blade depth tower 3760 can be used to assista practitioner of the invention in extending the blade extensions. Tower3760 includes ring 3762 which is assembled to shaft 3766. Shaft 3766includes two series of markings (each corresponding to a different sizedretractor) on shaft 3766. Ring 3762 is rotated, causing ring 3762 totranslated up or down the length of shaft 3766.

To use tower 3760 to extend the blades, a practitioner of the inventionrotates ring 3762 to a position along shaft 3766. The markings on shaft3766 are used to determine the desired position. As shown in FIG. 37I,retractor 3730 is directed over top end 3764 of shaft 3766 and down toring 3730. Top end 3764 engages the blade extensions of retractor 3730and extends them as retractor 3730 is directed down to ring 3762.

In some embodiments of the invention, the retractor is assembled to aninserter before insertion into a patient. FIG. 37J illustrates retractor3730 assembled to handle inserter 3768. Handle inserter 3768 isassembled to retractor 3730 by directing the attachment pins of inserter3768 into the attachment holes on the frame of retractor 3730. Onceassembled to inserter 3768, a practitioner of the invention usesinserter 3768 to direct retractor 3730 over the dilators and down tosurgical site 3708. During insertion, care should be taken to ensure thedilators remain fully seated on the facet so as to avoid creep of softtissue underneath the dilators.

Once inserted into patient 3702, one or more rigid arms 3770 can beattached or secured to retractor 3730, as illustrated in FIG. 37L. Rigidarm 3770 is secured to the surgical table and is attached to retractor3730 at one of the attachment holes on the expandable frame. Rigid arm3770 can be adjusted during the surgical procedure, thereby allowing apractitioner of the invention to direct retractor 3730 to a desiredposition.

Dilators 3706, 3710, 3712, and 3714 are removed from patient 3702, asillustrated in FIG. 37M. During removal of the dilators, care should betaken to ensure retractor 3730 remains fully seated against the laminaand facet to prevent creep of soft tissue.

In some embodiments of the invention, electrocautery is used to removeany remaining muscle attached to the bone inside of the insertedretractor, thereby preventing or reducing bleeding from the tissue. Thebone can be gently palpated with an inactive, extended length bone tipto ensure that it is against bone. A pituitary rongeur can be used topluck the fragments out of the exposure. Irrigation is optionally suedto ensure adequate visualization during these maneuvers.

Once retractor 3732 has been inserted and the dilators removed,retractor 3732 can be expanded using distracter instrument 3772, asillustrated in FIG. 37N. Retractor 3732 can be expanded in thecephlad-caudal and/or the medial-lateral directions by insertinginstrument 3772 into the top of retractor 3732 and squeezing the handleof instrument 3772 to the desired extent. The teeth of the lockingmechanism of the expandable frame allow for micro adjustment and willhold retractor 3732 at the expanded position. In some embodiments of theinvention, the distracter instrument is used parallel to the curvedracks to avoid undue stress on the retractor.

After retractor 3730 is expanded and the facet joint is visible, bladepusher 3774 may be used to deploy the telescoping blade extensionsfurther to, for example, prevent soft tissue creep in the working space.FIG. 37O illustrates a practitioner of the invention deploying theextensions with pusher 3774.

Optionally, the extensions can be removed and/or adjusted upward at anypoint of the surgical procedure. FIGS. 37P-37R illustrate a practitionerof the invention removing or adjusting a blade extension upward withblade remover 3776. FIGS. 37Q and 37R illustrate a close-up view ofremover 3776 engaging blade extension 3778. Blade remover 3776 isinserted into the tooth of telescoping blade extension 3778 and thehandle of remover 3776 is moved outward to relieve the locking mechanismof extension 3778, as illustrated in FIG. 37R. This allows extension3778 to be removed and/or adjusted upward, as illustrated in FIG. 37P.

If desired, additional blades and/or surgical instruments can beattached to retractor 3730. FIGS. 37S-37U illustrate such attachments.FIG. 37S illustrates the attachment of medial-lateral blade 3780 to aportion of retractor 3730 that includes an attachment point of a basecomponent of retractor 3730. FIG. 37T illustrates a top view ofretractor 3730 after blade 3780 assembled to retractor 3730. Blade 3780is secured to an attachment point and is supported by a portion of anarm. FIG. 37U illustrates light source 3782 attached to retractor 3730.If desired, light source 3782 is adjusted inward or outward, dependingon the amount of expansion of retractor 3730.

In some embodiments, this invention includes a surgical methodcomprising incising tissue of a mammal to create an incision, expandingthe incision to create a pathway from the incision to a surgical site,directing a retractor (e.g., a retractor of the invention) into thepathway, creating a working channel, and performing at least a portionof a surgical procedure through the working channel. The working channelcan be created by, for example, expanding the retractor by separating afirst retractor blade from a second retractor blade by moving at leastone of the first retractor blade and the second retractor blade along afirst connector of the retractor, and separating a third retractor bladefrom a fourth retractor blade by moving at least one of the thirdretractor blade and the fourth retractor blade along a second connector,wherein the second connector is oriented at an angle to the firstconnector.

In some embodiments, this invention provides methods of providing accessto vertebrae. In one embodiment, the method comprises incising tissue ofa mammal to create an incision, expanding the incision to create apathway from the incision to a surgical site, directing a retractor(e.g., a retractor of the invention) into the pathway, creating aworking channel through the retractor by separating at least tworetractor blades, performing at least a portion of a surgical procedurethrough the working channel at a first vertebra, exposing a secondvertebra that is adjacent to the first vertebra by directing aninstrument or implant between two of the retractor blades to displacetissue adjacent to the second vertebra; and performing at least aportion of a surgical procedure through the working channel at thesecond vertebra. The tissue adjacent to the second vertebra can bedisplaced by directing an instrument or implant between two of theretractor blades and cutting or moving the tissue away from near thesecond vertebra, thus allowing a practitioner to access two vertebraewithout the need to increase the incision in the skin of a mammal and/orcreate a second incision in the skin of a mammal.

In some embodiments, the first, second, third, and/or fourth retractorblades are moved along a nonlinear line (e.g., an acute line). In otherembodiments, the blades are moved along a linear line (i.e., a straightline).

In some embodiments, this invention includes a kit comprising a surgicalretractor, a retractor inserter that can be assembled to a frame of theretractor, a blade depth tower, a distracter, and at least one bladeadjustment instrument (e.g., one of the instruments mentionedpreviously, such as, for example, a blade remover instrument, a bladepusher instrument). In further embodiments, the kit includes at leastone obtruator and at least two dilators (e.g., two or more dilators ofdissimilar diameter). In still more embodiments, the kit includes atleast portions of an attachment device (e.g., portions of a rigidattachment arm).

1-21. (canceled)
 22. A surgical retractor, comprising: a first basecomponent having a first blade coupled thereto and a first connector armextending therefrom; a second base component having a second bladecoupled thereto and a second connector arm extending therefrom, thesecond base component being coupled to the first connector arm fortranslating motion with respect to the first base component; and a thirdbase component having a third blade coupled thereto and a thirdconnector arm extending therefrom, the third base component beingcoupled to the second connector arm for translating motion with respectto the first base component; the first, second, and third basecomponents being configured to define a major plane and to define anaccess portal through the major plane through which surgery can beperformed.
 23. The surgical retractor of claim 22, wherein at least oneof the first, second, and third connector arms curves out of the majorplane.
 24. The surgical retractor of claim 22, wherein each of thefirst, second, and third connector arms curves out of the major plane.25. The surgical retractor of claim 22, further comprising first,second, and third clips provided respectively on each of the first,second and third base components to couple the first, second, and thirdblades to the respective base components.
 26. The surgical retractor ofclaim 22, wherein the first connector arm is secured to the first basecomponent, the second connector arm is secured to the second basecomponent, and the third connector arm is secured to the third basecomponent.
 27. The surgical retractor of claim 26, further comprising afixing mechanism on the second base component for fixing the position ofthe second base component with respect to the first connector arm and afixing mechanism on the third base component for fixing the position ofthe third base component with respect to the second connector arm. 28.The surgical retractor of claim 27, wherein the first and secondconnector arms are ratchet arms and the fixing mechanisms on the secondand third components comprise a tab for engaging the respective ratchetarms.
 29. The surgical retractor of claim 28, wherein the first andsecond connector ratchet arms pass through an interior of the second andthird base components respectively, and the fixing mechanism tabsengaging the ratchet arms in the interior of the respective basecomponents.
 30. A surgical retractor, comprising: a first base componenthaving a first blade coupled thereto and a first connector arm extendingtherefrom; a second base component having a second blade coupled theretoand a second connector arm extending therefrom, the second basecomponent being coupled to the first connector arm for translatingmotion with respect to the first base component; a third base componenthaving a third blade coupled thereto and a third connector arm extendingtherefrom, the third base component being coupled to the secondconnector arm for translating motion with respect to the second basecomponent; and a fourth base component having a fourth blade coupledthereto and a fourth connector arm extending therefrom, the fourth basecomponent being coupled to the third connector arm for translatingmotion with respect to the third base component, the fourth connectorarm being coupled to the first base component for translating motionbetween the fourth and first base components; the first, second, third,and fourth base components being configured to define a major plane andto define an access portal through the major plane through which surgerycan be performed.
 31. The surgical retractor of claim 30, wherein atleast one of the first, second, third, and fourth connector arms curvesout of the major plane.
 32. The surgical retractor of claim 30, whereineach of the first, second, third, and fourth connector arms curves outof the major plane.
 33. The surgical retractor of claim 30, furthercomprising first, second, third, and fourth clips provided respectivelyon each of the first, second, third and fourth base components to couplethe first, second, third, and fourth blades to the respective basecomponents.
 34. The surgical retractor of claim 30, wherein at least twoof the first, second, third and fourth connector arms are secured totheir respective base components.
 35. The surgical retractor of claim30, wherein each of the first, second, third and fourth connector armsare secured to their respective base components.
 36. The surgicalretractor of claim 35, further comprising a fixing mechanism on thesecond base component for fixing the position of the second basecomponent with respect to the first connector arm, a fixing mechanism onthe third base component for fixing the position of the third basecomponent with respect to the second connector arm, a fixing mechanismon the fourth base component for fixing the position of the fourth basecomponent with respect to the third connector arm, and a fixingmechanism on the first base component for fixing the position of thefirst base component with respect to the fourth connector arm.
 37. Thesurgical retractor of claim 35, wherein at least two of the connectorarms are ratchet arms and the respective base components coupled to theratchet arms for translating motion each have a fixing mechanismcomprising a tab for engaging the respective ratchet arms.
 38. Thesurgical retractor of claim 37, wherein the ratchet arms pass through aninterior of the respective base components coupled to the ratchet armsfor translating motion and the fixing mechanism tabs engage the ratchetarms in the interior of the respective base components.
 39. The surgicalretractor of claim 36, wherein each connector arm is a ratchet arm. 40.The surgical retractor of claim 39, wherein each fixing elementcomprises a tab for engaging the respective ratchet arms.
 41. Thesurgical retractor of claim 40, wherein each ratchet arm passes throughan interior of the respective base components coupled to the ratchetarms for relative motion.
 42. The surgical retractor of claim 41,wherein each tab engages each ratchet arm in the interior of therespective base component.